Device for stacking letters and the like



Dec. 8, 1964 M. HENNEQUIN 3,160,293

DEVICE FOR STACKING LETTERS AND THE LIKE Filed Nov. 2 2, 1960 FIG.1

FIG. 3

WIT Al United States Patent 3,16%,293 DEVICE FGR STACKING LETTERS ANDTHE LIKE Maurice Henne uin Asnieres, France assi nor to Societe Thisinvention relates to the stacking of flat articles such as letters,cards, and the like, as they issue from machines of the types used e.g.far stamping, cancelling, or otherwise processing such articles, e.g.for postal purposes, from which machines said articles or lettersnormally issue, each disposed in a vertical plane. Throughout thespecification the articles handled by the stacking device of theinvention will be freguently referred to as letters for simplicity, itbeing understood that this designation is not to be interpreted aslimiting the scope of applicability of the invention, since this maywell be applied to any articles of generally fiat form capable of beingstacked. Such articles will, in the claims, be designated as articles ofthe type referred to.

The main object of the invention is to provide a device adapted forarranging such articles into neat stacks, regardless of the number ofarticles and hence the depth of the resulting stack, and regardless alsoof the dimensions of the articles, which may differ considerably fromone another.

The invention in one aspect is for apparatus for stacking fiat articlescomprising means for advancing the articles substantially single-fileand positioned in a generally vertical plane along a path, abutmentmeans arresting the advance of the articles at a predetermined positionof the path, means defining a supporting surface adjacent said positionand at an angle to said plane whereby the arrested articles will besupported against that surface in elementary stacks, and means forintermittently retractingthe supporting surface and for bodilytransferring the elementary stacks away from said position, and furtherabutment means for combining all the elementary stacks thus transferredinto a common pack.

In another aspect said apparatus may comprise means for advancing thearticles substantially single file, and positioned in a generallyvertical plane along a first path, means defining a second pathintersecting the first, abutment means on the first path beyond theintersection of both paths for arresting the articles as they areadvanced to said intersection, a transfer member positioned between saidpaths at their intersection, means for intermittently operating saidmember for repeatedly transferring a number of the arrested articlesfrom the first to the second path, and further abutment means on thesecond path against which all the transferred articles are adapted to besupported for combining into a common pack.

It will be appreciated that such apparatus does, in effect, handle thearticles in a manner similar to the natural process used in stackingletters by hand. That is, a persons instinctive procedure is to take upa small number of letters at a time and form an'elementary stacktherewith and then combine each such elementary stack with the mainstack previously built up.

In a preferred embodiment, the aforementioned means defining asupporting surface, or the transfer member, takes the form of arotatable circular disc formed with at least one deep cutout having oneside wall warped out of the plane of the disc so as to provide a vane inthe general form of a portion of a helicoid, projecting from the side ofthe disc against which each elementary stack is to be formed, and thecooperation of the cutout and vane during rotation of the disc providethe afore-specified means Patented Dec. 8, 1964 of retracting thetemporary supporting surface and transferring the elementary stacks.

The elementary stacks would normally, due to gravity, tend to fall overone another and become dislocated and thus prevent the formation of aneat final stack. To avoid this, according to another feature of theinvention, there is provided beyond the temporary supporting wall anhorizontal table having mounted on it a movable vertical plate againstwhich the final stack formed by the combination of the elementary stackswill be supported.

Further, in order to provide for a uniform degree of packing pressurethroughout the stack from start to finish of the stacking operations,there is provided in one form of the invention automatic means foradvancing the aforementioned plate supporting the main stack, whichmeans is controlled by way of a switch actuated by a pressureresponsiveelement sensing the packing pressure in the main stack.

An exemplary embodiment of the invention will now be described forpurposes of illustration but not of limitation with reference to theaccompanying drawings, where- FIG. 1 is a vertical section on line II ofFIG. 2 through a letter stacking device according to the invention;

FIG. 2 is a corresponding view in plan; and

FIG. 3 is a side view as seen along the arrow III of FIG. 2.

Articles, e.g. letters, to be stacked, one of which is shown at 1, arefed in vertical position by way of a channel track 2, e.g. the outputchannel from a cancelling ma chine, a stamping machine, a straighteningmachine, or any other processing device. 7

In the embodiment shown the letters rest with their bottom edges upon aconveyor belt 3 supported at its ends about drums or sheaves such as thedrum 4. Beyond the output end of the guide channel 2 there is provided aretainer system interposed on the path of travel of the articles. Thisretainer mechanism includes a pair of parallel spaced vertical guidewalls 8 and 9 which as seen in a horizontal view extend at a small angleto the direction of travel of the articles as determined by the guidechannel 2, and a retainer abutment or stop 11 serving as presentlydescribed for the intermittent and temporary retention of the articlesissuing from channel 2.

The wall 8 forms part of a stationary wall structure 12 including asshown an entrance guide wall portion 10 in alignment with a wall ofguide channel 2. Wall 9 on the other hand constitutes the temporarysupporting surface previously referred to and is formed by a rotary discmember rotatable on a horizontal shaft 14 in bearings 15 and 16 mountedon the top of structure 12.

Disc 9 is formed with a deep cutout 51 one side of which is bent orwarped out of the plane of the disc to provide a vane 18 of more or lesshelicoidal form projecting from the inner side of the disc 9 andextending generally in the sense of rotation of the disc, so that, inthe operation of the device, it acts in the manner of a screw to swallowup, so to speak, the articles fed to the inner side of the disc fromchannel 2. The relative inclination of the vane 18 is substantially thesame as the inclination of the walls 8 and 9 with respect to thedirection of travel of the lettersfrorn channel 2. It is necessary thatvane 18 of disc 9 move behind the articles fed to the inner side of thedisc from channel 2 to bring them to the front face of disc 9 as thesame rotates. There must be a free space between the sustained stackedarticles and the guiding means for consecutive articles. The free spaceis provided by a stack forming structure defined by generallylongitudinally extending wall 8 and the inner face of disc 9 which is inparallelism thereto and vertical generally transverse wall Walls 8 and11 together with the inner face of disc 9 define an article receivingtrough, as clearly shown in FIGURE 3 of the drawings. The axis of disc 9forms an angle of slightlymore than 90 with the axis of channel 2 sothat the flat inner face of disc 9 intersects the axis of channel 2,that is, the path of the incoming articles at a point ahead of theforward end of channel 2. The wall 8 of the article receiving trough isextended in the direction of channel'Z and by a vertical guide wall idin alignment with one side wall of channel 2 and this guide wall 10forms with the trough wall 8 the same angle as that formed by disc 9.with channel 2. The

entrance to the article receiving trough is thus of outwardly increasingsection. It will be apparent that the above describedarrangementoperates to form a stack of letters or like articles in thefollowing manner:

7 articles coming into engagement with the feeler.

Each consecutive letter or the like is moved along a straight pathdefind by channel 2 towards the entrance formed by the tapering guidesurfaces of wall it and the stack will actually contact the obliqueinner face of member 9 and that the other consecutive letters will beguided in the oblique direction each by a preceding letter received inthe trough-like chamber 8, 9, 11. v

The tapering walls 16' and 9' provide for a clearance space sufiicientto permit thevane 180i disc 9 to movebehind the stack 40.

Positioned in or approximately in the same plane as the plane of theupper surface of conveyor belt 3 is one end of a table 2.1 which extendsin general alignment with the rotational axis of disc 9. and in theso-called forward direction i.e. the direction of feed of the articlesto be stacked. A plurality of, herein three, endless chains 23,

'24, are disposed longitudinally of the table 21 with the upper lengthsof the endless chains projecting somewhat above the top surface of thetable. These chains serve to support the lower edges of the articles asthe 7 articles are stacked edgewise in a manner presently explained.

A foremost letter 1a of the stack generally designated 28 is appliedagainst a plate 29 arranged parallel to the disc 9. Preferably thesurface of table 21. slopes downward towards its free end so that thestack of letters will rest naturally against plate 29 by gravity. Theplate 29 is displaceable along the length of table by the action of themiddle chain 24 being connected with the latter through adrivingconnection such as a finger 31 depending from the plate andengaging between two adjacent links of the chain. A sleeve 33 projectingfrom a side of plate 29 is freely slidable on a rod 34 supported at itsends by a pair of arms 35, 36 projecting from the table 21, and servesto guide the plate 29 inits longitudinal displacements.

Disc 9 is driven in rotation at a suitable substantially uniform speedby any suitable m'otor'means not shown.

The chains 23, 24, 25 are intermittently driven, e.g. from an electricmotor and reducer unit 38 connected through shafting diagrammaticallyindicated at 42 to a shaft 41 having secured on it one 'of the endsprocket gears around which the endless chains are mounted.

Electric motor 38 is controlled through means responsive to the pressureof the stack of articles during the stack-forming process, so as tomaintain substantially a uniform compacting pressure in the stack as thelatter increases gradually in depth. For this purpose there is shown aswitch 44 connected in the energizing circuit of motor 38 and actuatedby an axially slidable plunger rod 45 the lower en of which is actuatedby a-feeler element 46 having one end pivoted on disc 9 at 47 andbiassed in the direction away from said disc and from' .chains 23, 24,25.

stopping motor 38 and the endless chains.

, The device is so adjusted that, for a predetermined pressure in thestack of letters 28, the feeler 46 actuates sliding rod 45 to operateswitch 44 and start the electric motor 38, thereby initiating a feeddisplacement of the The general operation of the system is thefollowing:

Assume the conveyor belt 3 is operated and the disc 9 revolving.Articles, such as letters 1 are fed one by one by way of guide channel 2and conveyed in between, the fixed retainer wall 8 and the surface ofdisc 9. During the time'required by one revolution of the disc a smallnumber of the letters are thus brought up and retained against the discand form a so-called elementary stack 4% of a convenient moderate depth.At that point in the revolution of disc 9 at which the vane 18 bearsdown upon this elementary stack, said vane engages behind the rear side.of a rearmost one of the letters in this stack and, as the vanecontinues its downward motion behind the elementary stack, this latteris automatically brought into engagement with the opposite sideof disc9, i.e. its front face, as itpasse's through the cutout 51 in the disc.Thus the cutout serves as a means for transiently retracting the activeportion of the disc surface, while the vane 18 acts, owingto itsinclined shape, to move the elementary stacksup against the general orfinal stack in process of formation.

Thus after one or more revolutions of the disc 9, the lettersconstituting an-elementary stack are advanced towards'the plate 29 andthere combine with the general stack 28 of letters previously advanced.When the compacity of the letters in stack'28 has attained a prescribedvalue the pressure exerted by the last letter in the stack againstfeeler 46 acts to operate switch 44, whereupon the chains 23, '24, 25are started in motion as previously described, and advance the plate 29against'the surface of which is applied a foremost letter 1a of stack28. f So long as the pressure in the pack exceeds the maximum prescribedvalue, motor 38 continues to be energized and the chains continue theirdisplacement. But as the pressure drops below said value the spring 48restores feeler 35' to. its idle position and switch 44 is opened, Theletters continue to advance in elementary stacks at each revolution ofthe disc, to build up the main pack 28, and as long as the pressure inthe pack has not again reached its prescribed value the chains remainstationary. However, whenever the pressure in the pack 28 becomesexcessive the motor 38 is again started and advances the chains toloosen the pack by the requisite amount.

It will thus readily be understood that the letters are very quickly andneatly stacked with a uniform cornpacity, and that satisfactoryoperationwill be obtained regardless of the dimensions of the letters (or otherarticles) and the rate of their delivery.

When the depth of the pack or stack is such as to occupy the fullavailable length of table 21, the pack is removed, and the plate 29 isreturned manually to a position adjacent disc 9 in readiness forreceiving a fresh pack of letters.

The invention clearly is not limited to the specific form of embodimentillustrated and described by way of example since many modifications maybe made therein without exceeding the scope of the invention, as bysubstituting for the revolving cut-out disc described some otherequivalent means for providing a temporary supporting wall adapted toarrest the articles to form elementary stacks, and periodically andintermittently retracting or removing such wall and allowing newlyformed the elementary stack to be advanced towards and combined with apreviously formed main stack or pack.

What is claimed is:

1. Apparatus for stacking flat articles comprising means supporting saidarticles in substantially single file and in a common generally verticalplane and for advancing the articles along a path in said plane,abutment means disposed generally transversely of the path of travel ofthe articles for arresting the articles at a predetermined position ofsaid path, a rotatable disc member having a flange surface adjacent saidposition and at an angle to said plane whereby the arrested articleswill be supported against said flange in elementary stacks, portions ofsaid disc defining a generally radially inwardly extending cutouttherein and one of said portions also defining a vane projecting from aside of said cutout towards said plane, and means for rotating saidmember in the direction of extension of said vane to, move the samebehind the arrested articles whereby at each revolution of the member anelementary stack of the articles will be drawn by said vane through saidcutout and removed from said position and combined into a common pack,and further abutment means positioned to support said common pack.

2. Apparatus for stacking fiat articles comprising means for advancingthe articles substantially single-file in a generally common verticalplane along a first path, means defining a second path intersecting thefirst path at an angle greater than 90 and means for supporting thearticles in stacked condition in parallel planes transverse to thesecond path to constitute a main pack, an abutment on the first pathbeyond the intersect-ion of said paths and generally transverselydisposed relative to said first path to arrest successive articles asthey advance to said intersection, a rotatable disc member having asurface adjacent said intersection and at an angle to said plane,portions of said disc defining a generally radially inwardly extendingcutout therein and one of said portions also defining a vane projectingfrom a side of said cutout towards said plane, and means for rotatingsaid disc member in the direction of extension of said vane to move thesame behind the articles arrested at said intersection whereby at eachrevolution said articles will be transferred from said first path to thesecond. path for building up said main pack thereon.

3. The apparatus claimed in claim 2 wherein said means for supportingthe articles in parallel stacked planes to constitute a main packcomprise an abutment member displaceable along said second path, meanssensing the packing pressure in said main pack, and means operated inresponse to the sensing means for displacing the abutment member tomaintain the packing pressure within a prescribed range.

4. The apparatus claimed in claim 3 wherein said sensing means comprisea movable feeler element connected to said flanged member and engagingan end article of said main pack so as to be moved in one direction onan increase in the pressure in said pack, means biassing said feelerelement in the opposite direction, and motor means operable to displacesaid abutment member and connected for control in response by theposition of said feeler element.

5. An apparatus for stacking flat articles comprising conveyor means tosupport said articles in substantially single file and in a commongenerally vertical plane and to advance the articles along a path insaid plane, first abutment means angularly disposed relative to the pathof travel of said articles to stop the same at a predetermined poistionto form a group thereof, a wall extending at right angles to said firstabutment means and in a direction toward the path of travel of saidarticles, a rotatable disc positioned adjacent said first abutment meansand having a planar face in parallel relation to said articles formingthe group and to said wall, a vane extending from said disc andengageable with the articles upon rotation thereof to transfer thearticles of the group to a table, means adjacent said conveyor to form amain group, a plate on said support means to support the main group ofarticles, said plate movable relative to said table in response to thepressure of the main group of articles, and means to detect the pressureof said main group to effect movement of said plate.

6. An apparatus for stacking fiat articles as defined in claim 10,wherein said table includes a plurality of longitudinally extendingendless chains in spaced parallel relation to each other, rotatableaxles mounted in said table and having sprockets fixed thereon aroundwhich said endless chains are mounted, said plate having meansoperatively connecting the same to one of said endless chains, and meansresponsive to said pressure detecting means to drive said axles andendless chains.

7; An apparatus for stacking flat articles comprising conveyor means tosupport said articles in substantially single file and in a commongenerally vertical planeand to advance the articles along a path in saidplane, first abutment means angularly disposed relative to the path oftravel of said articles to stop the same at a predetermined position toform a group thereof, a Wall extending at right angles to said firstabutment means and in a direction toward the path of travel of saidarticles, a rotatable disc positioned adjacent said first abutment meansand having a planar face in parallel relation to said articles formingthe group and to said wall, a vane extending from said disc andengageable with the articles upon rotation thereof to transfer thearticles of the group to a table, means adjacent said conveyor to form amain group, a plate on said support means to support the main group ofarticles, said plate movable relative to said table in response to thepressure of the main group of articles, and means to detect the pressureof said main group to effect movement of said plate, said rotatable discfurther including portions defining a centrally disposed openingtherein, a tubular axle fixed to said disc and having one end thereofpositioned in said opening, said pressure detecting means comprising afeeler element pivotally mounted on said disc and having a portionthereof extending transversely of said opening, means to bias saidfeeler element away from said disc and into engagement with the maingroup of articles, a switch adjacent the free end of said tubular axleand operatively connected to said drive means for said axles and endlesschains, a plunger rod slidably mounted in said tubular axle, one end ofsaid plunger rod being in engagement with said feeler element, the otherend of said plunger rod in engagement with said switch,

said feeler element pivoted in response to an increase in depth of saidmain group of articles to cause movement of said plunger rod to actuatesaid switch to operate said axle and endless chain drive means.

References Cited in the file of this patent UNITED STATES PATENTS790,157 Rose May 16, 1905 1,292,642 Pedn'ck Jan. 28, 1919 2,778,638Whillock Ian. 22, 1957 2,930,611 Pearce Mar. 29, 1960 3,018,009 OsborneIan. 23, 1962

1. APPARATUS FOR STACKING FLAT ARTICLES COMPRISING MEANS SUPPORTING SAIDARTICLES IN SUBSTANTIALLY SINGLE FILE AND IN A COMMON GENERALLY VERTICALPLANE AND FOR ADVANCING THE ARTICLES ALONG A PATH IN SAID PLANE,ABUTMENT MEANS DISPOSED GENERALLY TRANSVERSELY OF THE PATH OF TRAVEL OFTHE ARTICLES FOR ARRESTING THE ARTICLES AT A PREDETERMINED POSITION OFSAID PATH, A ROTATABLE DISC MEMBER HAVING A FLANGE SURFACE ADJACENT SAIDPOSITION AND AT AN ANGLE TO SAID PLANE WHEREBY THE ARRESTED ARTICLESWILL BE SUPPORTED AGAINST SAID FLANGE IN ELEMENTARY STACKS, PORTIONS OFSAID DISC DEFINING A GENERALLY RADIALLY INWARDLY EXTENDING CUTOUTTHEREIN AND ONE OF SAID PORTIONS ALSO DEFINING A VANE